Aeration apparatuses of the abovementioned type are known, for example, from German Patent 3,319,161 or German Patent 3,819,305, in which antechamber-like gas or compressed air spaces are provided as well as so-called flooding spaces, which are separate from the gas or compressed air spaces and can be flooded by the surrounding liquid. The gas or compressed air spaces are separated from the flooding spaces by various means, for example inserted partition walls or walls which are of one part with the basic bodies. It has been found that the known designs are not mechanically robust enough for use in waste water purifying plants, often exhibiting damage in the partition wall region. They are not suitable for practical continuous operation. Subdividing the basic body into a number of chambers makes the production expenditure for the known aeration apparatuses quite high. Closed-end flooding spaces produced by partition walls form dead zones, in which no liquid exchange takes place. To overcome these disadvantages, there has already been proposed an aeration apparatus of the type mentioned at the beginning, of which the supporting connection between the basic body and the compressed air supply pipe is substantially more stable and the overall design is more simple and consequently less expensive to produce than one of the known constructions. Serving in this case as connecting element between the basic body and the compressed air supply pipe is a supporting body having at least one axially directed air supply groove, which body extends with one end into the compressed air supply pipe and engages with its free end in a supporting manner into the basic body, providing a seal against the liquid. This design is not able, however, to connect a tubular hollow body to a compressed air supply pipe which has customary pipe connection nipples.